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Background: The transitional period between the oncosphere and the cysticercus of Taenia solium is the postoncospheral (PO) form, which has not yet been completely characterized. The aim of this work was to standardize a method to obtain T. solium PO forms by in vitro cultivation. We studied the morphology of the PO form and compared the expression of antigenic proteins among the PO form, oncosphere, and cysticerci stages. Methodology/Principal Findings: T. solium activated oncospheres were co-cultured with ten cell lines to obtain PO forms, which we studied at three stages of development–days 15, 30, and 60. A high percentage (32%) of PO forms was obtained using HCT-8 cells in comparison to the other cell lines. The morphology was observed by bright field, scanning, and transmission electron microscopy. Morphology of the PO form changed over time, with the six hooks commonly seen in the oncosphere stage disappearing in the PO forms, and vesicles and microtriches observed in the tegument. The PO forms grew as they aged, reaching a diameter of 2.5 mm at 60 days of culture. 15–30 day PO forms developed into mature cysticerci when inoculated into rats. Antigenic proteins expressed in the PO forms are also expressed by the oncosphere and cysticerci stages, with more cysticerci antigenic proteins expressed as the PO forms ages. Conclusions/Significance: This is the first report of an in vitro production method of T. solium PO forms. The changes observed in protein expression may be useful in identifying new targets for vaccine development. In vitro culture of PO form will aid in understanding the host-parasite relationship, since the structural changes of the developing PO forms may reflect the parasite’s immunoprotective mechanisms. A wider application of this method could significantly reduce the use of animals, and thus the costs and time required for further experimental investigations. [ABSTRACT FROM AUTHOR]

Bartonella species are emerging infectious organisms transmitted by arthropods capable of causing long-lasting infection in mammalian hosts. Among over 30 species described from four continents to date, 15 are known to infect humans, with eight of these capable of infecting dogs as well. B. bacilliformis is the only species described infecting humans in Peru; however, several other Bartonella species were detected in small mammals, bats, ticks, and fleas in that country. The objective of this study was to determine the serological and/or molecular prevalence of Bartonella species in asymptomatic dogs in Peru in order to indirectly evaluate the potential for human exposure to zoonotic Bartonella species. A convenient sample of 219 healthy dogs was obtained from five cities and three villages in Peru. EDTA-blood samples were collected from 205 dogs, whereas serum samples were available from 108 dogs. The EDTA-blood samples were screened by PCR followed by nucleotide sequencing for species identification. Antibodies against B. vinsonii berkhoffii and B. rochalimae were detected by IFA (cut-off of 1∶64). Bartonella DNA was detected in 21 of the 205 dogs (10%). Fifteen dogs were infected with B. rochalimae, while six dogs were infected with B. v. berkhoffii genotype III. Seropositivity for B. rochalimae was detected in 67 dogs (62%), and for B. v. berkhoffii in 43 (40%) of the 108 dogs. Reciprocal titers ≥1∶256 for B. rochalimae were detected in 19% of dogs, and for B. v. berkhoffii in 6.5% of dogs. This study identifies for the first time a population of dogs exposed to or infected with zoonotic Bartonella species, suggesting that domestic dogs may be the natural reservoir of these zoonotic organisms. Since dogs are epidemiological sentinels, Peruvian humans may be exposed to infections with B. rochalimae or B. v. berkhoffii. [ABSTRACT FROM AUTHOR]

The diagnosis of Chagas disease in humans is generally limited to the detection of specific antibodies. Detection of T. cruzi antigens in urine has been reported previously, but is not used in the diagnosis. In this study, soluble T. cruzi antigens and DNA were detected in urine samples and were associated with kidney injury and systemic detection of the parasite. We used 72 guinea pigs infected with T. cruzi Y strain and 18 non-infected guinea pigs. Blood, kidney, heart and urine samples were collected during the acute phase and chronic phase. Urine samples were concentrated by ultrafiltration. Antigens were detected by Western Blot using a polyclonal antibody against trypomastigote excretory-secretory antigen (TESA). T. cruzi DNA was detected by PCR using primers 121/122 and TcZ1/TcZ2. Levels of T. cruzi DNA in blood, heart and kidney were determined by quantitative PCR. T. cruzi antigens (75 kDa, 80 kDa, 120 kDa, 150 kDa) were detected in the acute phase (67.5%) and the chronic phase (45%). Parasite DNA in urine was detected only in the acute phase (45%). Kidney injury was characterized by high levels of proteinuria, kidney injury molecule-1 (KIM-1) and urea, and some histopathological changes such as inflammation, necrosis, fibrosis and scarce parasites. The detection of antigens and DNA in urine was associated with the presence of parasite DNA in blood and heart and with high levels of parasite DNA in blood, but not with the presence of parasite in kidney or kidney injury. These results suggest that the detection of T. cruzi in urine could be improved to be a valuable method for the diagnosis of Chagas disease, particularly in congenital Chagas disease and in immunocompromised patients. [ABSTRACT FROM AUTHOR]

Objective.: To explore the feasibility of developing a sheep model of neurocysticercosis (NCC) by intracranial infection with T. solium oncospheres., Materials and Methods.: We carried out an experimental infection model of NCC in sheep. Approximately 10 T. solium oncospheres previously cultured for 30 days were inoculated intracranially into ten sheep. The oncospheres, in 0.1 mL of physiological saline, were injected into the parietal lobe through an 18-gauge needle., Results.: After three months, granulomas were found in two sheep. In a third sheep we identified a 5 mm diameter cyst in the right lateral ventricle and histological evaluation confirmed that the cyst corresponded to a T. solium larva. Immunohistochemistry with monoclonal antibodies directed against membrane components and excretory/secretory antigens of the T. solium cyst was also used to confirm the etiology of the found granulomas. One of them showed reactivity to the monoclonal antibodies used, thus confirming that it was a cysticercus., Conclusion.: This experiment is the proof of concept that it is possible to infect sheep with cysticercosis by intracranial inoculation.